fix: skip auto refresh for disabled widgets

[jvsena42]

Closes #197

This PR skips auto-refresh for disabled widgets, saving resources by only syncing data for widgets that are actually enabled.

Description

The app was continuously syncing widget data in the background for all widgets, regardless of whether they were enabled. This wasted network and battery resources. Changes:

1. Replaces the always-on refresh logic with selective refresh based on enabled widget state
2. Tracks refresh jobs per widget type using a ConcurrentHashMap
3. Starts/stops refresh coroutines dynamically when widgets are enabled/disabled
4. Adds manual refresh when opening widget preview screens (since disabled widgets won't auto-refresh)

Preview

Screen_recording_20260130_103016.webm

QA Notes

1. Enable widget - coroutine starts

1. Enable a widget from settings
2. Check logs - should see "Updated $widgetType widget successfully"
3. Verify widget data refreshes periodically

2. Disable widget - coroutine stops

1. Disable a widget from settings
2. Check logs - should see "Stopped refresh coroutine for [TYPE]"
3. Verify no more network requests for that widget

3. Preview screen refresh

1. Open each preview screen (News, Facts, Blocks, Weather, Price)
2. Verify fresh data loads
3. Confirm no errors in logs

[claude]

Code Review

Issue: Missing Throwable parameter in Logger call

Location: app/src/main/java/to/bitkit/repositories/WidgetsRepo.kt:196

The Logger call in the .onFailure block should include the Throwable parameter e as the second positional argument to capture error details.

According to CLAUDE.md, Logger calls within .onFailure blocks should pass the Throwable:

.onFailure {
    Logger.error("Failed", it, context = TAG)
}

Current code:

.onFailure { e ->
    Logger.verbose("Failed to update $widgetType widget", context = TAG)
}

Should be:

.onFailure { e ->
    Logger.verbose("Failed to update $widgetType widget", e, context = TAG)
}

This ensures error details are properly captured in logs.